Water contract indicator

ABSTRACT

The present invention discloses an adhesive article. The adhesive article comprises a first layer comprising a transparent film, the first layer having a first major surface and a second major surface. Additionally, the adhesive article comprises a second layer comprising a fluid transport substrate, the second layer having a first major surface and a second major surface, the first major surface of the second layer being in contact with the second major surface of the first layer and a third layer comprising a fluid transportable ink, the third layer being associated with the second major surface of the second layer. The adhesive article then comprises an adhesive layer.

FIELD OF THE INVENTION

The present invention relates to adhesive articles having the capabilityto detect fluid, especially water, exposure.

BACKGROUND OF THE INVENTION

An adhesive article, for example a tape or a label that indicates fluidexposure is desirable for many uses. For example, such an adhesivearticle may help detect minor leaks in water tight pipes. Additionally,these adhesive articles may be useful for detecting water exposure ofelectronics, especially hand-held electronics. For example, an adhesivearticle that indicates water exposure would be useful for manufacturersof electronic devices, for example cellular phones, personal digitalassistants, hand held computers, battery chargers, or small electricappliances, to help determine functional failure. The adhesive articlemay be placed on the electronic device, either within the electronicportion of the device or on an external casing. If the device had beenimmersed or a sensitive component contacted with a fluid, such as water,the warranty could be voided or the cause of failure determined.

Some adhesive articles used for fluid indication describe a layer of inkon a substrate. The ink is displayed in a pattern that is altered uponexposure to water. For example, the ink may be in stripes or dots, whichblur upon exposure to water. Some additional adhesive articles have atransparent cover film to prevent smudging of the ink prior to waterexposure. Other adhesive articles utilize an ink that changes color uponthe exposure to water.

SUMMARY OF THE INVENTION

Some commercially available adhesive articles indicate too easily underhigh humidity conditions. Some additional commercially availableadhesive articles may not indicate water contact at all after exposureto high humidity conditions. What is desired is a water indicatingadhesive article that will indicate upon sustained water exposure, butdoes not indicate in a high humidity environment.

The present invention discloses an adhesive article. The adhesivearticle comprises a first layer comprising a transparent film, the firstlayer having a first major surface and a second major surface.Additionally, the adhesive article comprises a second layer comprising afluid transport substrate, the second layer having a first major surfaceand a second major surface, the first major surface of the second layerbeing in contact with the second major surface of the first layer and athird layer comprising a fluid transportable ink, the third layer beingassociated with the second major surface of the second layer. Theadhesive article then comprises an adhesive layer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a first embodiment of the invention.

FIG. 2 is a cross-sectional view of a second embodiment of theinvention.

FIG. 3 is a perspective view of the embodiment shown in FIG. 2.

FIG. 4 is a digitally recorded micrograph showing example 3 during highhumidity exposure as detailed below.

DETAILED DESCRIPTION OF THE INVENTION

An embodiment of the fluid indicating adhesive article is illustrated inFIG. 1. The adhesive article 10 comprises a fluid transport substrate 12having a first major surface 14 and a second major surface 16. A fluidtransportable ink layer 18 is coated onto the second major surface 16 ofthe substrate 12. The ink layer has a first major surface 20 and asecond major surface 22. The first major surface 20 of the ink layer 18is in contact with the second major surface 16 of the substrate 12. Theadhesive article 10 additionally comprises an adhesive layer 24 appliedonto the second major surface 22 of the ink layer 18.

The adhesive article 10 additionally comprises a transparent layer 26laminated onto the first major surface 14 of the substrate 12. Theadhesive article 10 also comprises a release liner 28 set on theadhesive layer 24 opposite the second major surface 22 of the ink layer18.

Another embodiment of the invention is illustrated in FIG. 2. Theadhesive article 30 comprises a substrate 32 having a first majorsurface 34 and a second major surface 36. An ink layer 38 is coated ontothe second major surface 36 of the substrate 32. The ink layer has afirst major surface 40 and a second major surface 42. The first majorsurface 40 of the ink layer 38 is in contact with the second majorsurface 36 of the substrate 32. The adhesive article 30 additionallycomprises an adhesive layer 44 applied onto the second major surface 42of the ink layer 38.

The adhesive article 30 additionally comprises a transparent layer 46.The transparent layer 46 as illustrated in FIG. 2 comprises atransparent film 47 and a transparent layer adhesive layer 48. Thetransparent layer adhesive layer 48 is in contact with the first majorsurface 34 of the substrate 32. The adhesive article 30 also comprises arelease liner 50 set on the adhesive layer 44 opposite the second majorsurface 42 of the ink layer 38. The transparent layer adhesive layer 48extends past the substrate 32 and is in contact with the release liner50.

The transparent layer 46, the substrate 32, and the ink layer 38 definea hole 52. The hole 52 exposes the ink layer 38 to an outer surface 54of the adhesive article 30.

Details of the components of the adhesive article of the presentinvention are further described below.

Substrate

The fluid indicating adhesive article of the present invention includesa substrate capable of fluid transport (“fluid transport substrate”.) Afluid transport substrate will transport fluid through the substrate.For example, the substrate may comprise a microporous film as describedin U.S. Pat. No. 5,238,623 to Mrozinski, which is incorporated byreference. In many embodiments, the fluid transport substrate is afibrous substrate. The fibrous substrate is generally capable ofabsorbing a fluid. However, the fibrous substrate generally will notsaturate in a high humidity environment. In certain embodiments, thesubstrate is a water absorbent substrate. The water absorbent substrateis generally made of a material that maintains a cohesive form when wet.Suitable substrates include paper, such as cellulose based paper, forexample paper towels and copy grade paper.

Additionally, woven and nonwoven fabrics and polyolefins may be suitablesubstrates. Polyolefins may be treated to enhance fluid absorbance, forexample by treating with a hydrophilic coating or blending thepolyolefin with a hydrophilic fiber. However, any coating used to makethe polyolefin hydrophilic should be chosen so it will not interferewith, or react negatively to the adhesive chosen. Melt-blown or spunbondtechniques can be employed to make such nonwoven webs. Nonwoven webs canalso be prepared, for example, on a RANDO WEBBER (Rando Corporation,Macedon, N.Y.) air-laying machine or on a carding machine.

Representative examples polyolefins include, for example, polypropylene,polyethylene, high density polyethylene, low density polyethylene,linear low density polyethylene, and linear ultra low densitypolyethylene, and polybutylenes. Additional materials that may be usefulfor the substrate of the present invention include nylon, polyester(e.g., polyethylene terephthalate), vinyl copolymers, such as polyvinylchlorides, both plasticized and unplasticized, and polyvinyl acetates;olefinic copolymers, such as ethylene/methacrylate copolymers,ethylene/vinyl acetate copolymers, acrylonitrile-butadiene-styrenecopolymers, and ethylene/propylene copolymers; acrylic polymers andcopolymers; polycaprolactones; and combinations of the foregoing.Mixtures or blends of any plastic or plastic and elastomeric materialssuch as polypropylene/polyethylene, polyurethane/polyolefin,polyurethane/polycarbonate, polyurethane/polyester, can also be used.

Specific examples of suitable substrates include a cellulose paper, suchas Westvaco Ultrasorb FP “matte,” absorbent cellulose paper commerciallyavailable from Westvaco Corp. of Wickliffe, Ky. The substrate may alsobe a standard weight copy paper, such as paper sold under the tradenameCOPYPLUS Standard White, available from International Paper, Memphis,Tenn.

In many embodiments, the water absorbent substrate is flat. Thesubstrate may be clear, white, or any color. Generally, the substrate isopaque when dry, so the layers under the substrate are not visible. Inmany embodiments, the substrate is permanently opaque, even when wet.

Fluid Transportable Ink

Fluid transportable ink is coated onto one surface of the substrate toform an ink layer. Ink is defined as a dispersion of a pigment or a dyesolution produced as a fluid, paste or a powder. Upon exposure to afluid, the fluid transportable ink is mobilized and flows with the fluidthrough the substrate. In some embodiments, a hole in the substrateexposes the ink and assists in the displacement of the ink in the eventof fluid exposure.

For example, a water soluble ink is suitable for the present invention.In specific embodiments, the ink may be HP Ink Jet cartridge 51649aprinted blue ink, commercially available from Hewlett Packard Co.,Boise, Id. Other examples include blue dye powder sold under thetradename HIDACID AZURE Blue dustless 20DA2228 commercially availablefrom B. F. Goodrich, Cincinnati, Ohio and red dye sold under thetradename FASTUSOL Red 43LN commercially available from BASF Corp. ofMount Olive, N.J.

The ink may be dispersed on the substrate. In other embodiments, the inkis dispersed on the adhesive layer, which is then brought into contactwith the substrate. The ink may be dispersed using various coating andprinting techniques chosen to be suitable for a particular ink. Forexample, the ink may be dispersed using an ink jet printer, gravureprinting, flexographic printing, letter press printing or powder coatingtechniques. The ink may be dispersed on the substrate in a variety ofcoverage, for example a predetermined pattern, a random pattern, orcomplete coverage.

Adhesive

An adhesive layer is applied, for example coated or laminated, onto thesurface of the ink layer. The adhesive may be any adhesive, for examplea thermally bondable (hot-melt) adhesive or an ultra-violet activatedadhesive. Generally, the adhesive layer is a pressure sensitiveadhesive. Pressure sensitive adhesives are generally characterized bytheir properties. Pressure sensitive adhesives are well known to one ofordinary skill in the art to possess properties including the following:(1) aggressive and permanent tack, (2) adherence to a substrate with nomore than finger pressure, (3) sufficient ability to hold onto anadherend, and (4) sufficient cohesive strength to be removed cleanlyfrom the adherend. Many pressure sensitive adhesives must satisfy theseproperties under an array of different stress rate conditions. Additivesmay be included in the pressure sensitive adhesive to optimize thecharacteristics of the pressure sensitive adhesive.

Any suitable pressure sensitive adhesive composition can be used forthis invention. Generally, the pressure sensitive adhesive should notinterfere with the ability of the ink to transport with a fluid, forexample by reacting with a treatment on the substrate. The pressuresensitive adhesive component can be any material that has pressuresensitive adhesive properties. Furthermore, the pressure sensitiveadhesive component can be a single pressure sensitive adhesive or thepressure sensitive adhesive can be a combination of two or more pressuresensitive adhesives.

Pressure sensitive adhesives useful in the present invention include,for example, those based on natural rubbers, synthetic rubbers, styreneblock copolymers, polyvinyl ethers, poly (meth)acrylates (including bothacrylates and methacrylates), polyolefins, and silicones.

The pressure sensitive adhesive may be inherently tacky. If desired,tackifiers may be added to a base material to form the pressuresensitive adhesive. Useful tackifiers include, for example, rosin esterresins, aromatic hydrocarbon resins, aliphatic hydrocarbon resins, andterpene resins. Other materials can be added for special purposes,including, for example, oils, plasticizers, antioxidants, ultraviolet(“UV”) stabilizers, hydrogenated butyl rubber, pigments, and curingagents.

In one embodiment, the pressure sensitive adhesive is based on at leastone poly(meth)acrylate (e.g. is a (meth)acrylic pressure sensitiveadhesive). Poly(meth)acrylic pressure sensitive adhesives are derivedfrom, for example, at least one alkyl (meth)acrylate ester monomer suchas, for example, isooctyl acrylate, isononyl acrylate, 2-methyl-butylacrylate, 2-ethyl-hexyl acrylate and n-butyl acrylate; and at least oneoptional co-monomer component such as, for example, (meth)acrylic acid,vinyl acetate, N-vinyl pyrrolidone, (meth)acrylamide, a vinyl ester, afumarate, a styrene macromer, or combinations thereof. Generally, thepoly(meth)acrylic pressure sensitive adhesive is derived from betweenabout 0 and about 20 weight percent of acrylic acid and between about100 and about 80 weight percent of at least one of isooctyl acrylate,2-ethyl-hexyl acrylate or n-butyl acrylate composition, preferablyisooctyl acrylate. A suitable embodiment for the present invention isderived from between about 2 and about 10 weight percent acrylic acidand between about 90 and about 98 weight percent of at least one ofisooctyl acryl ate, 2-ethyl -hexyl acryl ate or n-butyl acryl atecomposition.

The adhesive layer is applied onto the ink layer using any suitablecoating or laminating technique. For example, the adhesive layer may beformed by continuous forming methods, including hot melt coating,drawing or extruding, the adhesive composition from the elongating shearforce device (e.g. a draw die, a film die, or a rotary rod die) andsubsequently contacting the drawn adhesive composition to a moving web(e.g. plastic) or other suitable substrate. A related continuous formingmethod involves extruding the adhesive composition and a co-extrudedbacking material from a film die and cooling the layered product to forman adhesive tape. Other continuous forming methods involve directlycontacting the adhesive composition to a rapidly moving web or othersuitable preformed substrate. Using this method, the adhesivecomposition is applied to the moving preformed web using a die havingflexible die lips, such as a rotary rod die. The adhesive layer mayadditionally be formed by any non-continuous coating method.

Alternatively, the adhesive may be prepared by dissolving the componentsof the adhesive composition in a solvent such as toluene and castingover the substrate.

Transparent Layer

The water indicating adhesive article of the present inventionadditionally has a transparent layer comprising a transparent film onthe fluid transporting substrate. The transparent layer is on thesubstrate surface opposite the ink layer. The transparent layer mayextend beyond the edge of the substrate, or may be the same size as thesubstrate. Generally such a layer may be waterproof. Such a layerprotects the water indicating adhesive article from moisture duringhuman handling and from dew/condensation. Additionally, the additionallayer may protect the water indicating adhesive article during prolongedsubmersion and may extend the life of certain water indicating tapesduring humidity aging conditions. In certain embodiments, thetransparent layer is printable using a variety of printing techniques,including ink-jet printing, thermal transfer printing and flexographicprinting. In addition, the transparent layer may be a multi-layerdecorative film such as, for example, those disclosed in U.S. Pat. No.6,117,530 to Jonza et al.

The transparent layer may have an adhesive layer, as detailed in FIG. 2,to adhere the transparent layer to the substrate. Alternatively, thetransparent layer may be adhered to the substrate by high temperaturelamination, thus eliminating the need for an adhesive layer between thesubstrate and the transparent layer. The transparent layer serves toprotect the adhesive article surface from dirt, debris, and handlingcontaminants as well as holding the color within the paper when theindicator is immersed in water for long periods. When an adhesivearticle without a protective film is immersed for long periods of time,one potential problem is that it will bleed out or wash out and start toturn back to the original, non-indicating color (white); thus giving afalse reading that it was not exposed to water. Also, depending upon thematerial of the substrate, an adhesive article without a protective filmmay begin to disintegrate if immersed for long periods of time. However,an adhesive article with a protective cover film will hold the colorchange in the paper and will not bleed out or disintegrate after longperiods of time immersed. Specific examples of transparent layerssuitable for the present invention include UPVC backed tapes, such asthose sold under the tradename Scotch Premium Transparent Film Tape 600;polypropylene tapes such as those sold under the tradename Scotch BoxSealing Tape 375 and polyester backed tapes such as those sold under thetradename Scotch Box Sealing Tape 355, or 3M™ Thermal TransferImprintable Film Tape 7861; all commercially available from 3M Companyof St. Paul, Minn.

Additional Layers

The water indicating tape of the present invention may compriseadditional layers. For example, some embodiments comprise an additionalfluid transport substrate layer between the adhesive layer and the inklayer. The water indicating tape may also comprise a release liner, suchas silicone coated paper or film, adhered to the adhesive until the tapeis ready to be adhered to a surface.

If the tape is sold in a roll, it may be beneficial to add a releasematerial (e.g., low adhesion backsize) to the side of the tape oppositethe adhesive.

Method of Manufacture

The water indicating adhesive article of the present invention ismanufactured generally by coating a substrate as described with a fluidtransportable ink. The substrate may be in the form of a sheet, or maybe a long strip suitable for rolling the final product into a roll oftape. The ink may be coated to completely cover the substrate, or may becoated in segments or a design. The ink must be coated so that the inkdoes not bleed through the substrate. For example, the ink may be coatedonto a release liner, and then transferred to the substrate.

Adhesive is then applied to the ink as described above. The substrateand the ink may then be completely coated with the adhesive, or may becoated with segments of adhesive. Such a segmented adhesive may bedesirable in embodiments where the substrate may have a coating that maybe affected by the adhesive. The adhesive is then covered with a releaseliner if desired.

In other embodiments, the adhesive can be made into a transfer tape bycoating the adhesive composition, either completely or in segments, on aliner, or between two liners, coated with a release coating. If thetransfer tape is made by coating between two liners, one of the linersof the transfer tape can be removed to expose the adhesive surface. Theadhesive surface may then be applied to the ink layer, or the adhesivesurface may be coated with the fluid transportable ink and thenlaminated to the substrate. The remaining release liner aids intransferring the adhesive to the substrate.

Individual labels may be created by converting the sheets intoindividual labels, for example by die cutting the sheet. The sheet maybe die cut into any size or shape, such as circles or squares. Forexample, the sheet may be die cut into a circle with a diameter greaterthan 5 millimeters for ease of handling. Specific examples includerectangles used for an informative label, or small circles placed insidean electronic device.

The transparent layer may be laminated or adhered to the substrate priorto converting the substrate into an individual label. In separateembodiments, the transparent layer is added to the adhesive articleafter conversion, for example in embodiments as depicted in FIG. 2wherein the transparent layer extends beyond the edge of the substrate.The embodiment illustrated in FIGS. 2 and 3 may be manufactured bycutting a label, for example by die cutting, around the existingadhesive article, creating an overlap of the transparent film as seen inFIGS. 2 and 3.

Use of the Adhesive Article

The adhesive article of the present invention may be a roll of tape. Theadhesive article may also be an individual label. In these embodiments,the adhesive article is placed on a device, such as a portableelectronic device. In some embodiments, the adhesive article is printed,for example the adhesive article could include warranty information inaddition to acting as an indicator for fluid exposure.

Upon exposure to a fluid, the adhesive article of the present inventionexposes to indicate the fluid contact. Depending on the ink and thesubstrate used in the adhesive article, the fluid could include polarsolvents such as alcohol, non-polar solvents, bodily fluids and water.Generally, the adhesive article can indicate exposure to a fluid if theink is soluble in the fluid and the fluid transports through thesubstrate. Specifically, the invention is beneficial to indicate theexposure to fluids containing water, such as consumable alcoholicdrinks.

Objects and advantages of this invention are further illustrated by thefollowing examples. The particular materials and amounts thereof, aswell as other conditions and details, recited in these examples shouldnot be used to unduly limit this invention.

EXAMPLES

Item Description Supplier Substrate B Westvaco Ultrasorb FP WestvacoCorporation of “matte,” absorbent, cellulose Wickliffe, Kentucky paperSubstrate C Hammermill CopyPlus Copy International Paper of Paper, 8½″ ×11″, 84 Memphis, Tennessee Brightness Ink - Blue Inkjet “Blue” from HPInkjet Hewlett Packard Co., of cartridge 51649a Boise, Idaho Ink - RedFASTUSOL Red 43LN BASF Corp of Mount Olive, New Jersey Laminating 3M ™467MP Roll 3M Company of St. Paul, Adhesive Laminating AdhesiveMinnesota Transparent Scotch ™ Premium 3M Company of St. Paul,Protective Film Transparent Film Tape 600 Minnesota Transparent 3M ™Thermal Transfer 3M Company of St. Paul, Protective Film ImprintableFilm Label Minnesota Material 7861, 2.0 mil Gloss Clear PolyesterThermal Transfer, 0.8 mil 300 high strength acrylic adhesive, 3.2 mil55# densified Kraft liner Transparent 3M ™ Thermal Transfer 3M Companyof St. Paul, Protective Film Imprintable Film Label Minnesota Material7876, 2.0 mil Gloss Clear Polyester Thermal Transfer, 1.8 mil 350 highstrength acrylic adhesive, 3.2 mil 55# densified Kraft linerMaterials:

The following examples describe the making and testing of a watercontact indicator. It is understood that in all the examples, the orderof the process may be altered to achieve the same final construction ofthe various embodiments of the present invention.

First Embodiment of the Invention Examples of the First Embodiment

Example 1 was prepared by taking a sheet of Ultrasorb FP “matte,”absorbent, cellulose paper, referred to here as Substrate B, and cuttingit into a separate master sheet to fit into an Inkjet printer, modelHewlett Packard DeskJet 692C. Substrate B has a caliper thickness ofapproximately 5.8 mil (0.147 mm), a Sheffield porosity value ofapproximately 25 seconds and opacity of approximately 92%. The papersubstrate was then solid printed over the entire surface of one sidewith a water-soluble blue colored ink, HP Inkjet “Blue” using a model692C Hewlett Packard DeskJet. The printed side of the paper waslaminated to a laminating adhesive using 3M™ 467MP Roll LaminatingAdhesive, 2.0 mil (50 microns) #200MP “Hi-Performance” Acrylic Adhesivewith a 4.0 mil (100 microns) release liner of 58# Tan Polycoated KraftPaper. Scotch® Premium Transparent Film Tape 600, was applied to thenon-printed side of the paper.

Individual water contact indicators were then created from the mastersheet by die cutting the sheet into 13-mm diameter circles, although anysize and shape indicator could be prepared, by standard convertingsteps.

Example 2 was prepared in the same manner as example 1, with theexception that an 8½×11 inch (21.6 cm×27.9 cm) piece of HammermillCopyPlus Copy Paper, was used instead of the Ultrasorb FP “matte,”absorbent, cellulose paper.

Example 3 was prepared in the same fashion as example 1, except that thepaper substrate was gravure printed with FASTUSOL Red 43LN red ink priorto the application of the laminating adhesive.

Example 4 was prepared exactly as example 1, however instead of theScotch® Premium Transparent Film Tape 600, the transparent cover sheetused was 3M™ Thermal Transfer Imprintable Film Label Material 7876, 2.0mil Gloss Clear Polyester Thermal Transfer, 1.8 mil 350 high strengthacrylic adhesive.

Example 5 was prepared exactly as example 1, however instead of theScotch® Premium Transparent Film Tape 600, the transparent cover sheetused was 3M™ Thermal Transfer Imprintable Film Label Material 7861, 2.0mil Gloss Clear Polyester Thermal Transfer, 0.8 mil 300 high strengthacrylic adhesive.

Several replicates of each of the above examples were generated fortesting and evaluation purposes. The examples were tested for theirindicating functionality under conditions of high humidity and totalwater contact. To test for sensitivity to a high humidity environment, anumber of replicates of each example were stored hanging vertically in acontrolled temperature/humidity chamber at 158° F. (70° C.)/90% relativehumidity. At periodic intervals, individual replicates of the variousexamples were removed from the temperature/humidity chamber andevaluated for their change in color using a HUNTERLAB Labscan 6000Spectrocolorimeter, available from Hunter Associates Laboratory, Inc.,of Reston, Va. Data was obtained by following test method Tappi T 524om-94, measuring the change in the darkness of a color in terms of an Lvalue where the L scale is defined as 100 being white and 0 being black.

Examples

Example Description 1 Paper “B”, ink jet printed blue, #600 cover film 2Copy paper, ink jet printed blue, #600 cover film 3 Paper “B”, gravureprinted red ink, #600 cover film 4 Paper “B”, ink jet printed blue,#7876 cover film 5 Paper “B”, ink jet printed blue, #7861 cover film

TABLE 1 HUMIDITY EXPOSURE vs. WATER CONTACT Humidity Conditions: 70°C./90% Relative Humidity Data: Exam- 144 288 Water Contact* ple 0 hrs 5hrs 24 hrs 48 hrs hrs hrs Value (1 min) 1 89.58 89.09 86.16 81.87 77.5 —57.90 2 86.81 83.74 76.34 71.54 — — 62.51 3 88.90 89.85 89.32 89.34 —88.35 49.24 “L” Scale Data: “L” scale denotes color shade change fromwhite = 100 to black = 0 *Contact of samples for 1 minute in water. “—”Not measured at these time points.

TABLE 2 RELATIVE CHANGE IN SAMPLE DARKNESS FROM ORIGINAL AFTER EXPOSURETO HUMIDITY AND IMMERSION % Change Water Contact vs. % Change WaterHumidity color Example Humidity Contact change factor 1 13.5% 35.4% 2.62 17.6% 28.0% 1.6 3 0.6% 44.6% 74.3

The data in Table 1 shows that most examples exhibit a slight colorchange with prolonged exposure to high humidity. Table 2 shows therelative change in indicator darkness in L values from the 0-time pointto the time of longest humidity exposure for all samples and relative towater contact for 1 minute. Table 2 indicates that all samples remain ina generally non-indicating condition after exposure to high humidity.However, the L value for examples after water contact is much lower,indicating much darker, than the L value for examples exposed to highhumidity. This is also clearly illustrated by FIG. 4, where example 3,after 288 hours of exposure to high humidity, is essentially unchanged,but after just 1 minute of water contact, there is a dramatic change inthe darkness of the color of example 3.

Table 3 demonstrates the potential problem with “washout.” ComparativeExample A was made as described for Example 3, without a transparentlayer. After total immersion in water for 48 hours, Comparative ExampleA, which has no protective film has reached an indication plateau, evenslightly less indication from 24 hours to 48 hours. The indicating inkhas begun to “washout.” Whereas, example 3, which has a protective coverfilm, holds the color change and continues to strongly indicateimmersion even after extended exposure.

TABLE 3 EXTENDED TOTAL IMMERSION EXPOSURE Example 0 hrs 4 hrs 24 hrs 48hrs Comp. 91.34 73.69 69.12 70.57 Ex. A 6 89.14 77.04 65.5  55.41Example Description Comp. Paper “B”, gravure printed red ink, Noprotective film Ex. A 6 Paper “B”, gravure printed red ink, #600 coverfilm

TABLE 4 HUMIDITY EXPOSURE OF SAMPLES WITH VARIOUS PROTECTIVE FILMS -Humidity Conditions: 70° C./ 90% Relative Humidity Water Contact*Example 0 hrs 24 hrs 72 hrs 168 hrs Value (1 min) 4 88.59 85.94 83.4179.62 51.76 5 89.35 86.95 80.96 76.24 49.17 Example Description 4 Paper“B”, ink jet printed blue, #7876 cover film 5 Paper “B”, ink jet printedblue, #7861 cover film “L” Scale Data: “L” scale denotes color shadechange from white = 100 to black = 0 *Water Contact of samples for 1minute in water.

Second Embodiment of the Invention

Another embodiment of the water contact indicator of the presentinvention includes the following modification to the general embodimentdescribed in examples 1-5. The ink is applied to the substrate sheet ina pattern such as parallel stripes or lines that are about 0.25 inchwide each, rather than a solid printed pattern over the entire surfaceof one side. The striped printed side of the substrate is then laminatedto a laminating adhesive, as in examples 1-8. The sheet is then cut orslit into strips, each wider than the width of the printed stripe. Thus,leaving a non-printed area on each side of the stripe. A transparentprotective film is then applied to the non-printed side in a manner suchthat the transparent protective film covers and is wider than the widthof the strip of substrate. This strip construction of water contactindicator can then be cut at any length for application. Indication willhappen at the newly cut strip ends where the paper edge is not coveredby the transparent protective film and so may be exposed to water.

Third Embodiment of the Invention

As in examples 1-5 of the first embodiment, ink applied to a substratesurface. Also, the printed side of the substrate is then laminated to alaminating adhesive with a liner. This construction is then die cut incircular shapes and the non-circular shaped matrix paper and adhesive isremoved leaving only the die cut printed substrate circles on the liner.A transparent protective film or laminate is then laminated over the diecut parts and exposed liner. Next, another die cut conversion process isperformed to leave the printed substrate circle centrally located withinthis second die cut and having the transparent cover extending equallyaround the paper. At this point no edge or portion of the printed papercircle is exposed. These die cut parts are then perforated with adie-punched hole in the center of the individual circular water contactindicator. This die-punched hole perforates the protective film layerand the substrate layer, down to the printed ink layer. When thisembodiment of the water contact indicator is exposed to water, the holeacts as an access to the indicator where the water is absorbed andindication is observed. The size of the die-punched hole is small enoughto minimize “false” contact indications due to high humidity.

Various modifications and alterations that do not depart from the scopeand spirit of this invention will become apparent to those skilled inthe art. This invention is not to be unduly limited to the illustrativeembodiments set forth herein.

1. An adhesive article comprising a first layer comprising a transparentfilm, the first layer having a first major surface and a second majorsurface opposite the first major surface; a second layer comprising afluid transport substrate, the second layer having a first major surfaceand a second major surface opposite the first major surface, the firstmajor surface of the second layer being in contact with the second majorsurface of the first layer; a third layer comprising a fluidtransportable ink, the third layer having a first major surface and asecond major surface, the first major surface being in contact with thesecond major surface of the second layer; and an adhesive layer incontact with the second major surface of the third layer.
 2. Theadhesive article of claim 1 wherein the substrate is fibrous.
 3. Theadhesive article of claim 1 wherein the substrate is water absorbent. 4.The adhesive article of claim 1 wherein the substrate is porous.
 5. Theadhesive article of claim 1 wherein the substrate is a cellulose-basedpaper.
 6. The adhesive article of claim 1 wherein the first layercompletely covers the second layer.
 7. The adhesive article of claim 1having a hole through the first layer, exposing the second layer.
 8. Theadhesive article of claim 1 having a hole through the first and secondlayers, exposing the third layer.
 9. The adhesive article of claim 1wherein the third layer completely covers the second major surface ofthe second layer.
 10. The adhesive article of claim 1 wherein the fluidtransportable ink comprises a water soluble ink.
 11. The adhesivearticle of claim 1 wherein the fluid transportable ink comprises apowder dye.
 12. The adhesive article of claim 1 wherein the transparentlayer comprises a waterproof transparent film.
 13. The adhesive articleof claim 1 wherein the first layer further comprises an adhesive. 14.The adhesive article of claim 1 wherein the first layer furthercomprises a release coating.
 15. The adhesive article of claim 1comprising a release liner on the adhesive layer.
 16. The adhesivearticle of claim 1 comprising a fluid transport substrate between thethird layer and the adhesive layer.
 17. The adhesive article of claim 1wherein the first major surface of the first layer is printable.
 18. Alabel comprising a first layer comprising a transparent film, the firstlayer having a first major surface and a second major surface oppositethe first major surface; a second layer comprising a fluid transportsubstrate, the second layer having a first major surface and a secondmajor surface opposite the first major surface, the first major surfaceof the second layer being in contact with the second major surface ofthe first layer; a third layer comprising a fluid transportable ink, thethird layer having a first major surface and a second major surface, thefirst major surface being in contact with the second major surface ofthe second layer; an adhesive layer in contact with the second majorsurface of the third layer; and a printed layer on the first majorsurface of the first layer.